From the answer:
Thanks for your quick response, manousheh.... I would have to agree that having a "Pay Deposit" or "Pay Invoice in Full" buttons on an e-invoice is convenient for you and your customers.

From the answer:
Thanks for giving us additional details of your concern, MrsPSmith.... From the information you've provided, it sounds like you've sent an e-invoice to your customer and they clicked on the "Pay Now" button to make a payment.